Starfish Life Cycle: Lesson for Kids

Instructor: Mark Boster
Most people know about the life cycles of pets, like puppies or kittens, that are born, grow up and have their own children, then get old and die. But people don't usually know what goes on under the sea. Let's learn about the life cycle of a starfish.

Sandy Starfish

Hello, I am Sandy Starfish. Some people prefer to call me a sea star because I'm not actually a fish.

I welcome you to my home on the floor of the ocean. I'm going to tell you about when I was a baby starfish. I will also share my life into adulthood, eating, having babies, and death. Are you ready?

When I Was a Baby

When I was first fertilized in the ocean, I floated around with many other small animals. I was only about one millimeter long. I know, that is pretty small! I would float around and eat things smaller than myself.

For a few weeks there, I didn't eat at all. I didn't even look like a starfish yet, I just floated around until I fell to the bottom of the ocean. I was just a larva. When I landed on the floor, I began to become rounder and grew arms out of my center. That is when I grew and became the starfish you know today.

Sandy Scrapbook Page 1

Just an Arm

I have a friend, who began its life as an arm! Yes, an arm. Did you know that starfish are regenerative? That means that we can regrow parts that come off or lose. So if I lose a leg, a new leg will grow there. The leg I lost will also grow a new starfish. I bet you can't do that.

Sandy Scrapbook Page 2

Dinner Time, Sandy

I am getting hungry and will eat some of my favorite foods: mussel, snails, oysters, and clams. I use the suction cups on the bottom of my legs to pull them apart. Then I do something really strange. I turn my stomach inside out. That way I can eat some food that is bigger than me. If the food is small enough I just keep my stomach inside. I also use the suction cups on the bottom of my tube feet to get around to find my food.

Sandy Scrapbook Page 3


The first thing you need to know about starfish having babies is that there's no touching. Sometimes starfish can have babies all by themselves. You see, some of us are not male or female, we are both. If I have babies by myself that is called asexual reproduction. Most of us make babies this way. We do this by squirting out eggs and then squirting out the sperm that fertilizes them.

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